Alkyl sulfonates of polyvinyl alcohol as viscosifiers in saline solutions

Abstract

There are provided alkyl sulfonate salts derived from polyvinyl alcohols which are viscosifiers, e.g., for enhanced oil recovery fluids and for use in drilling fluids.

I claim: 
     
       1. In a method for the recovery of oil from a subterranean oil reservoir penetrated by spaced injection and production systems in which an aqueous mobility control slug is introduced into said reservoir via said injection system to displace oil to said production system, the improvement comprising employing in said slug a thickening amount of a polymeric alkyl sulfonate salt of the formula   H--R.sub.1 --H                                             (I)     wherein R 1  represents repeating polymeric units, said units consisting essentially of (i) units of the formula ##STR7## and (ii) units of the formula ##STR8## having a mer % sufficient to impart enhanced brine solubility and thickening characteristics thereto, wherein:   (a) R 2  --O is ethyleneoxy, propyleneoxy or mixtures thereof;   (b) n is zero or greater, provided that (R 2  --O) n  has 18 or less carbon atoms;   (c) R 3  is a hydrocarbyl group having between 2 and 6 carbon atoms; and   (d) M is a cation.   
     
     
       2. A method according to claim 1, wherein R 2  is CH 2  CH 2  or CH 2  CH 2  CH 2  and n is 0.6. 
     
     
       3. A method according to claim 1, wherein n is zero and M is monovalent cation. 
     
     
       4. A method according to claim 3, wherein said repeating polymeric units further contain units of the formula ##STR9## 
     
     
       5. A method according to claim 3, wherein said repeating polymeric units consist essentially of from about 5% to about 40% of said units of formula (III) the remainder of said units being essentially of formula (II). 
     
     
       6. A method according to claim 1, wherein said units of the formula (III) are of the formula ##STR10## 
     
     
       7. A method for maintaining the proper viscosity of an aqueous brine drilling completion fluid used when drilling reaches a producing formation at a depth between 15 and 30 thousand feet, the temperature of said formation being more than about 325° F., said method comprising incorporating in said fluid a viscosity increasing amount of a polymeric alkyl sulfonate salt of the formula   H--R.sub.1 --H                                             (I)     wherein R 1  represents repeating polymeric units, said units consisting essentially of (i) units of the formula ##STR11## and (ii) units of the formula ##STR12## having a mer % sufficient to impart enhanced brine solubility and thickening characteristics thereto, wherein:   (a) R 2  --O is ethyleneoxy, propyleneoxy or mixtures thereof;   (b) n is zero or greater, provided that (R 2  --O) n  has 18 or less carbon atoms;   (c) R 3  is a hydrocarbyl group having between 2 and 6 carbon atoms; and   (d) M is a cation.   
     
     
       8. A method according to claim 7, wherein R 2  is CH 2  CH 2  or CH 2  CH 2  CH 2  and n is 0-6. 
     
     
       9. A method according to claim 7, wherein n is zero and M is a monovalent cation. 
     
     
       10. A method according to claim 9, wherein said repeating polymeric units further contain units of the formula ##STR13## 
     
     
       11. A method according to claim 9, wherein said repeating polymeric units consist essentially of from about 5% to about 40% of said units of formula (III) the remainder of said units being essentially of formula (II). 
     
     
       12. A method according to claim 7, wherein said units of the formula (III) are of the formula ##STR14##